linux/fs/ocfs2/dlmfs/userdlm.h
Joel Becker 0016eedc41 ocfs2_dlmfs: Use the stackglue.
Rather than directly using o2dlm, dlmfs can now use the stackglue.  This
allows it to use userspace cluster stacks and fs/dlm.  This commit
forces o2cb for now.  A latter commit will bump the protocol version and
allow non-o2cb stacks.

This is one big sed, really.  LKM_xxMODE becomes DLM_LOCK_xx.  LKM_flag
becomes DLM_LKF_flag.

We also learn to check that the LVB is valid before reading it.  Any DLM
can lose the contents of the LVB during a complicated recovery.  userdlm
should be checking this.  Now it does.  dlmfs will return 0 from read(2)
if the LVB was invalid.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-02-26 15:41:18 -08:00

113 lines
3.3 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* userdlm.h
*
* Userspace dlm defines
*
* Copyright (C) 2002, 2004 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef USERDLM_H
#define USERDLM_H
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/workqueue.h>
/* user_lock_res->l_flags flags. */
#define USER_LOCK_ATTACHED (0x00000001) /* we have initialized
* the lvb */
#define USER_LOCK_BUSY (0x00000002) /* we are currently in
* dlm_lock */
#define USER_LOCK_BLOCKED (0x00000004) /* blocked waiting to
* downconvert*/
#define USER_LOCK_IN_TEARDOWN (0x00000008) /* we're currently
* destroying this
* lock. */
#define USER_LOCK_QUEUED (0x00000010) /* lock is on the
* workqueue */
#define USER_LOCK_IN_CANCEL (0x00000020)
struct user_lock_res {
spinlock_t l_lock;
int l_flags;
#define USER_DLM_LOCK_ID_MAX_LEN 32
char l_name[USER_DLM_LOCK_ID_MAX_LEN];
int l_namelen;
int l_level;
unsigned int l_ro_holders;
unsigned int l_ex_holders;
struct ocfs2_dlm_lksb l_lksb;
int l_requested;
int l_blocking;
wait_queue_head_t l_event;
struct work_struct l_work;
};
extern struct workqueue_struct *user_dlm_worker;
void user_dlm_lock_res_init(struct user_lock_res *lockres,
struct dentry *dentry);
int user_dlm_destroy_lock(struct user_lock_res *lockres);
int user_dlm_cluster_lock(struct user_lock_res *lockres,
int level,
int lkm_flags);
void user_dlm_cluster_unlock(struct user_lock_res *lockres,
int level);
void user_dlm_write_lvb(struct inode *inode,
const char *val,
unsigned int len);
ssize_t user_dlm_read_lvb(struct inode *inode,
char *val,
unsigned int len);
struct ocfs2_cluster_connection *user_dlm_register(struct qstr *name);
void user_dlm_unregister(struct ocfs2_cluster_connection *conn);
void user_dlm_set_locking_protocol(void);
struct dlmfs_inode_private {
struct ocfs2_cluster_connection *ip_conn;
struct user_lock_res ip_lockres; /* unused for directories. */
struct inode *ip_parent;
struct inode ip_vfs_inode;
};
static inline struct dlmfs_inode_private *
DLMFS_I(struct inode *inode)
{
return container_of(inode,
struct dlmfs_inode_private,
ip_vfs_inode);
}
struct dlmfs_filp_private {
int fp_lock_level;
};
#define DLMFS_MAGIC 0x76a9f425
#endif /* USERDLM_H */